The hcall H_GET_PERF_COUNTER_INFO with counter request value as PROCESSOR_CONFIG(0X90), can be used to get the system processor configuration information. To expose the system processor config information, patch adds sysfs file called "processor_config" to the "/sys/devices/hv_gpci/interface/" of hv_gpci pmu driver.
Add macro for PROCESSOR_CONFIG counter request value in hv-gpci.h file. Also add a new function called "sysinfo_device_attr_create", which will create and add required device attribute to the interface_attrs array. The processor_config sysfs file is only available for power10 and above platforms. Add a new macro called INTERFACE_PROCESSOR_CONFIG_ATTR, which points to the index of NULL placefolder, for processor_config attribute in the interface_attrs array. Also add macro INTERFACE_NULL_ATTR which points to index of NULL attribute in interface_attrs array. Signed-off-by: Kajol Jain <kj...@linux.ibm.com> --- arch/powerpc/perf/hv-gpci.c | 110 +++++++++++++++++++++++++++++++++--- arch/powerpc/perf/hv-gpci.h | 5 +- 2 files changed, 107 insertions(+), 8 deletions(-) diff --git a/arch/powerpc/perf/hv-gpci.c b/arch/powerpc/perf/hv-gpci.c index bca24725699e..c9fe74373e5f 100644 --- a/arch/powerpc/perf/hv-gpci.c +++ b/arch/powerpc/perf/hv-gpci.c @@ -237,6 +237,72 @@ static ssize_t processor_bus_topology_show(struct device *dev, struct device_att return ret; } +static ssize_t processor_config_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct hv_gpci_request_buffer *arg; + unsigned long ret; + size_t n = 0; + + arg = (void *)get_cpu_var(hv_gpci_reqb); + memset(arg, 0, HGPCI_REQ_BUFFER_SIZE); + + /* + * Pass the counter request value 0x90 corresponds to request + * type 'Processor_config', to retrieve + * the system processor information. + * starting_index value implies the starting hardware + * processor index. + */ + ret = systeminfo_gpci_request(PROCESSOR_CONFIG, 0, 0, buf, &n, arg); + + if (!ret) + return n; + + if (ret != H_PARAMETER) + goto out; + + /* + * ret value as 'H_PARAMETER' corresponds to 'GEN_BUF_TOO_SMALL', which + * implies that buffer can't accommodate all information, and a partial buffer + * returned. To handle that, we need to take subsequent requests + * with next starting index to retrieve additional (missing) data. + * Below loop do subsequent hcalls with next starting index and add it + * to buffer util we get all the information. + */ + while (ret == H_PARAMETER) { + int returned_values = be16_to_cpu(arg->params.returned_values); + int elementsize = be16_to_cpu(arg->params.cv_element_size); + int last_element = (returned_values - 1) * elementsize; + + /* + * Since the starting index is part of counter_value + * buffer elements, use the starting index value in the last + * element and add 1 to subsequent hcalls. + */ + u32 starting_index = arg->bytes[last_element + 3] + + (arg->bytes[last_element + 2] << 8) + + (arg->bytes[last_element + 1] << 16) + + (arg->bytes[last_element] << 24) + 1; + + memset(arg, 0, HGPCI_REQ_BUFFER_SIZE); + + ret = systeminfo_gpci_request(PROCESSOR_CONFIG, starting_index, 0, buf, &n, arg); + + if (!ret) + return n; + + if (ret != H_PARAMETER) + goto out; + } + + return n; + +out: + put_cpu_var(hv_gpci_reqb); + return ret; +} + static DEVICE_ATTR_RO(kernel_version); static DEVICE_ATTR_RO(cpumask); @@ -258,6 +324,11 @@ static struct attribute *interface_attrs[] = { * attribute, set in init function if applicable. */ NULL, + /* + * This NULL is a placeholder for the processor_config + * attribute, set in init function if applicable. + */ + NULL, NULL, }; @@ -463,21 +534,46 @@ static int hv_gpci_cpu_hotplug_init(void) ppc_hv_gpci_cpu_offline); } -static void add_sysinfo_interface_files(void) +static void sysinfo_device_attr_create(int sysinfo_interface_group_index) { - struct device_attribute *attr = kzalloc(sizeof(*attr), GFP_KERNEL); + struct device_attribute *attr; + if (sysinfo_interface_group_index < INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR || + sysinfo_interface_group_index >= INTERFACE_NULL_ATTR) { + pr_info("Wrong interface group index for system information\n"); + return; + } + + attr = kzalloc(sizeof(*attr), GFP_KERNEL); if (!attr) { - pr_info("Memory allocation failed for processor_bug_topology interface file\n"); + pr_info("Mem allocation failed, sysinfo index:%d\n", sysinfo_interface_group_index); return; } - /* Add processor_bus_topology attribute in the interface_attrs attribute array */ sysfs_attr_init(&attr->attr); - attr->attr.name = "processor_bug_topology"; + + switch (sysinfo_interface_group_index) { + case INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR: + attr->attr.name = "processor_bug_topology"; + attr->show = processor_bus_topology_show; + break; + case INTERFACE_PROCESSOR_CONFIG_ATTR: + attr->attr.name = "processor_config"; + attr->show = processor_config_show; + break; + } + attr->attr.mode = 0444; - attr->show = processor_bus_topology_show; - interface_attrs[INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR] = &attr->attr; + interface_attrs[sysinfo_interface_group_index] = &attr->attr; +} + +static void add_sysinfo_interface_files(void) +{ + /* Add processor_bus_topology attribute in the interface_attrs attribute array */ + sysinfo_device_attr_create(INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR); + + /* Add processor_config attribute in the interface_attrs attribute array */ + sysinfo_device_attr_create(INTERFACE_PROCESSOR_CONFIG_ATTR); } static int hv_gpci_init(void) diff --git a/arch/powerpc/perf/hv-gpci.h b/arch/powerpc/perf/hv-gpci.h index ff76bc010823..0d324a7c684b 100644 --- a/arch/powerpc/perf/hv-gpci.h +++ b/arch/powerpc/perf/hv-gpci.h @@ -24,10 +24,13 @@ enum { }; /* Counter request value to retrieve system information */ -#define PROCESSOR_BUS_TOPOLOGY 0XD0 +#define PROCESSOR_BUS_TOPOLOGY 0XD0 +#define PROCESSOR_CONFIG 0X90 /* Interface attribute array index to store system information */ #define INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR 6 +#define INTERFACE_PROCESSOR_CONFIG_ATTR 7 +#define INTERFACE_NULL_ATTR 8 #define REQUEST_FILE "../hv-gpci-requests.h" #define NAME_LOWER hv_gpci -- 2.35.3